E M A R G I N U L A. 



Plate I. 



Genus EMAKGINULA, LaiwuH-. 



Testa jialdliformk, plus minusive conica, plenimqu, 

 ovata, apice recurvo, radiatim costellata vel sul- 

 cata ; costd vel sulcos dorsali in Jlxsurum vel it 

 simim parvum ad manjinem anticum dcsinenti. 



Shell patellitbrm, more or less conical, generally ovate, | 

 with apex recurved, radiately grooved or sulcated; 

 dorsal rib or groove ending in fissure or small 

 sinus at the anterior margin. 



In place of the " key-hole" at the apex which 

 characterizes the genus Fissurella, there is in shells of I 

 the genus Emarjinula a cicatrix forming a grooved 

 ridge, when distinct, running from the apex to the 

 anterior margin and terminating either in an incised 

 slit, or a more or less perceptible sinus. The Emar- 

 ginulce are iirincipally inhabitants of deep water, the 

 larger number being obUiined by dredging on the 

 shores of Australia, the Philippines and West Indies. 

 There are three British and several Mediterranean 

 species. 



Species 1. (Fig. a, b, c, d, Mus. Brit., &c.) 



Emap.ginula i'.ugusa. Etna, testa ovatd, oblique conica, 

 viridi, fuscoque varie radiatd et pictd ; costis 

 radiantibus elevatis, distantibus, aspervlatis, cum 

 minoribus interstialibus, et liris conccntricis valide 

 canceJlatd ; margine intus a-cnulato, jissurd pro- 

 funda. 



The rugose Emarginula. Shell ovate, obliquely 

 conical, rayed and painted variously with green 

 and brown, strongly cancellated with elevated, 

 distant, roughened radiating ribs, with smaller 

 interstitial ones, and concentric ridges ; margin 

 crenulated within, fissure deep. 



QooT. Voyage de 1' Astrolabe. 



Clypidina acuminata, A. Adams. 



Clypidina Candida, A. Adams. 



Clypidina annulata, A. Adams. 



Clypidina fungina, Goidd. 

 Clypidina conoidca, Gould. 

 Clypidina aspera, Gould. 

 Emaiyiniila conoidea. Reeve. 

 Hub. Australia. 



The long array of synonyms here cited results from 

 the great variation of form and condition to which this 

 species seem to bo liable, and to the extent of wearing 

 to which the sculpture has been exposed in different 

 individuals. 



Spec 



(Fig. a, h, Mus. Brit, and Sowerby.) 



Emarginula tenuicostata. Ema. testa ovatd, j isciis 

 vi7-idis vel radiis fuscis pictd, costis numerosis, 

 noduliferis, et striis cmcentiicis minutis crebre 

 cancellatd; apice versus marginem posticim in- 

 curvo ; fissurd profunda, ijicisd. 



The thin-ridbed Ehahginula. Shell ovate, painted 

 with green bands or brown rays, closely cancel- 

 lated with numerous beaded ribs and minute 

 concentric ridges; apex curved inwards towards 

 the posterior margin ; fissure deep, imised. 



Sowerby. Thesaurus Conchyliorum, Fissurellida, Emar- 

 ginula, Sp. 32, fig. 17, 18. 



Hab.^ ? 



Species 3. (Fig. a, b, Mus. Brit.) 



Emarginula depressa. Ema. testa lata, depressd, 

 quinquelaterali, subviridi, costis crassis, nodosis, 

 quarum quinque majoribus radiatd; costd dorsali 

 brevi, elevatd, fssm-d extics inconspicud; apice 

 postico. 



The depressed Emarginula. Shell broad, depressed, 

 five-sided, greenish, rayed with thick, knobbed 

 ribs, of which five are larger ; dorsal rib short, 



August, 1874. 



